hashing password using brcrpt in "pre" - node.js

Question

i am trying to store a hash of the password entered in a form using bcrypt in mongodb
this is the form
<form action="/register" method="POST">
<label for="firstname">Firstname</label>
<input type="text" name="firstname" id="fname" ></p><br/>
<label for="lastname">Lastname</label>
<input type="text" name="lastname" ></p><br/>
<label for="email">Email</label>
<input type="email" name="email" ></p><br/>
<label for="">Password</label>
<input type="password" name="password" ></p><br/>
<input type="submit" value="submit">
this is my mongoose schema
const userschema = new mongoose.Schema({ // define a schema
fname:{type:String,trim:true},
lname:{type:String,trim:true},
email:{type:String,lowercase:true,trim:true},
pass:{type:String}
});
and this is my pre function that is to be performed before save is called in my handler
userschema.pre('save',async function(next){
const user=this;
console.log(user); //in this log the user object this is containing plaintext value of password
await bcrypt.hash(user.pass, 8, function(err, hash) {
if(err){throw new Error(err);}
else{
user.pass=hash;
console.log(user); //and in this log the user object is containing hashed value as expected
}
})
next()}
);
and this is my handler for saving the user in the database
app.post("/register",function(req,res){
const errors = validationResult(req);
if (!errors.isEmpty()) {
console.log(errors.array());
return res.status(400).render("register",{ errors: errors.array() });
}
console.log(req.body); //out of context question but for some reason only firstname and email are visible in req.body object can anybody body explain
const usave=new user({
fname:req.body.firstname,
lname:req.body.lastname,
email:req.body.email,
pass:req.body.password
})
usave.save((err,doc)=>{
if(err){res.send(err);}
else{
res.send("success");}
});
});
when the route is handled the user is being saved succesfully but the password stored in the database is not being hashed.
I did make user.pass=hash in the schema.pre('save') function but its not being stored in the database as hash just being stored as plain text
can anybody tell me what is wrong with this code?how do i save the hashpassword to database?

Answer 1

userschema.pre('save', async function(next) {
var user = this;
await bcrypt.hash(user.pass, 8, function(err, hash) {
if (err) {
return next(err);
}
user.pass = hash;
next();
})
});
The above code will accomplish your goal of always hashing the password when a document is saved to the DB, passwords are not hashed until the document is saved.